Imaging with the 130pds

[Rob F]

Finally going to tackle some improvements to my 130, I’ve ordered flocking material and will also order the TS flange to cover the mirror clips.

 I might also chop down the focus tube. I have to first find the focus distance for using my 1100d canon, already marked the location using my OSC camera. 
I figure since I’ll have to take the scope apart I might as well make all the mods at the same time. 

[Space Oddities]

For anyone interested, I recently ordered a 3D printed copy of this mask, designed to block the stray lights coming from the back. It fits perfectly!

The material I selected might be a bit fragile though, perhaps I didn't select the best material and density for the job, but I don't know anything about 3D printing... Let's see if it holds!

Skywatcher 130PDS Primary Mirror Back Cover by RolandKol - Thingiverse

[Jamgood]

5 hours ago, Space Oddities said:

For anyone interested, I recently ordered a 3D printed copy of this mask, designed to block the stray lights coming from the back. It fits perfectly!

The material I selected might be a bit fragile though, perhaps I didn't select the best material and density for the job, but I don't know anything about 3D printing... Let's see if it holds!

Skywatcher 130PDS Primary Mirror Back Cover by RolandKol - Thingiverse

I had one of them that I got with another 130PDS bundle I bought and used it on my scope for a time. While it worked at blocking the stray lights, I found that it to be the cause of really slow cool down periods for the primary mirror. Not too bad if you keep the scope outside but if you move from indoor to out, especially in the winter, it was a nuisance that more than doubled the cooling period or left you with thermal spikes in your images.. A black shower cap does the same job but is easily removable for cooling. YMMV.

Edited June 12, 2022 by Jamgood

[Space Oddities]

I usually setup the scope early, but in winter that might be an issue indeed. Good to know thanks!

 

[Pitch Black Skies]

On 31/05/2022 at 20:17, edarter said:

It does come out if the back focus yes, but a 10mm extension ring solves that and moves the recessed part of the baader out of the way of the securing screws on the focus tube. That's one of of the causes of slight tilt with the baader.... So kills 2 birds with one stone.

I'm sure there must be a way of working out how much of the primary you would lose by pushing it up the OTA 10mm but I can't figure out the maths on that.

I'm also researching whether a screw in fixing on the end of the focus tube is lower profile than the original, if so it would further reduce the focus tube protrusion meaning even less requirement to move the primary up the OTA.

Sorry, just seen your message now. Yes, that's a very good idea actually.

Yes I would be interested to know the maths on that too. Why not just try the longer screws and see how you find it? You can very easily revert back if it doesn't work out well.

Edited June 16, 2022 by Pitch Black Skies

[edarter]

8 hours ago, Pitch Black Skies said:

Why not just try the longer screws and see how you find it? You can very revert back if it doesn't work out well.

Thats what I'm planning, but not got round to yet

[Rob F]

I bought some m48 extensions and removed the Baader m48 collar. It makes a huge difference, the focus tube ow only protrudes about 7mm into the ota. Im glad I tried this first before chopping the focus tube.

First image before doing flocking, primary baffle and 10mm m48 extension. Second image after all mods and m48.

[Ratlet]

10 hours ago, Rob F said:

I bought some m48 extensions and removed the Baader m48 collar. It makes a huge difference, the focus tube ow only protrudes about 7mm into the ota. Im glad I tried this first before chopping the focus tube.

First image before doing flocking, primary baffle and 10mm m48 extension. Second image after all mods and m48.

Could explain how you've got your imaging train setup to get focus without massive ptrusion into the tube or post a picture of how it is different?

As I understand it you're new setup allowed you to put the baader cc further into the focus tube so it needs to be wound in less?

Are you still using a compression fitting to hold the cc or is it all screwed together?

Is this with your osc or DSLR?

[Bibabutzemann]

9 hours ago, Ratlet said:

Could explain how you've got your imaging train setup to get focus without massive ptrusion into the tube or post a picture of how it is different?

As I understand it you're new setup allowed you to put the baader cc further into the focus tube so it needs to be wound in less?

Are you still using a compression fitting to hold the cc or is it all screwed together?

Is this with your osc or DSLR?

Combination of those two should work for a DSLR setup:

https://www.firstlightoptics.com/offers/offer_ts-ultra-short-t2-adapter-for-canon-eos-1mm-length_299370.html

https://www.amazon.de/Svbony-Verlängerungsrohr-Verlängerung-Brennweite-Astrofotografie/dp/B07S72HT9R/ref=asc_df_B07S72HT9R/?tag=googshopde-21&linkCode=df0&hvadid=501171454772&hvpos=&hvnetw=g&hvrand=12580399997129093878&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9041990&hvtargid=pla-876062391525&psc=1&th=1&psc=1(only the 10mm extension tube is needed)

This reduces the protrusion by 10mm.

Im not sure if i will buy this though. It adds 60€. Maybe i would rather sell my MPCC and buy the GPU CC instead.

Edited June 18, 2022 by Bibabutzemann

[Rob F]

11 hours ago, Ratlet said:

Could explain how you've got your imaging train setup to get focus without massive ptrusion into the tube or post a picture of how it is different?

As I understand it you're new setup allowed you to put the baader cc further into the focus tube so it needs to be wound in less?

Are you still using a compression fitting to hold the cc or is it all screwed together?

Is this with your osc or DSLR?

I am using a compression fitting, and my camera is the PlayerOne Neptune C. I swapped the m42 extension for m48 and removed the m48 knurled Baader ring. This allows the cc to go further into the focus tube roughly 10mm. The m48 extension ring is now held by the compression ring , instead of the cc. I have a step down m48 to m42 connecting the m48 to the camera., back focus is 57.5mm

In this image I have tape on the m48 extension to roughly mark the focus point.

Edited June 18, 2022 by Rob F

[Ratlet]

Cheers Rob and Bib.  That's what I thought you had 😊.

I'm planning broadly the same thing when I eventually get the 130pds later this year (nice thing about being this far north, there is [removed word] all actual night).

From what I've read the tilt issues with the baader mpcc are largely due to the slope on the cc and the 2 screws on the SW focus tube.  I was going to upgrade to focus tube to have a compression anyway.

How you getting on with the player one camera Rob?  They look excellent and I think for a lot of people they'll be a major upgrade from DSLR, especially in cooler climates.  I'm think of the Saturn, though maybe next year.

[Rob F]

1 hour ago, Ratlet said:

Cheers Rob and Bib.  That's what I thought you had 😊.

I'm planning broadly the same thing when I eventually get the 130pds later this year (nice thing about being this far north, there is [removed word] all actual night).

From what I've read the tilt issues with the baader mpcc are largely due to the slope on the cc and the 2 screws on the SW focus tube.  I was going to upgrade to focus tube to have a compression anyway.

How you getting on with the player one camera Rob?  They look excellent and I think for a lot of people they'll be a major upgrade from DSLR, especially in cooler climates.  I'm think of the Saturn, though maybe next year.

I love the PlayerOne camera, I have the Neptune C and plan on getting the new Saturn C (imx533 sensor). As for tilt, the PlayerOne has screws to adjust tilt.

My M51 was taken with PlayerOne, 60s subs for 10.5hrs total.

[Jim Smith]

Crescent Nebula NGC6888

130 pds - Baader MPCC III - AZ-EQ5 GT - ASI 533 MCP - Altair triband filter

best 108 of 120x30s unguided - Gain 200  - uncropped

Some slightly wonky corner stars. Might increase spacing a bit.

[Jim Smith]

Elephant's Trunk Nebula IC1396A

130 pds - Baader MPCC III - AZ-EQ5 GT - ASI 533 MCP - Altair triband filter

best 108 of 120x30s unguided - Gain 200  - uncropped

I think the extra backspacing has helped the corners. 

[Jim Smith]

Dumbbell Nebula M27

 

130 pds - Baader MPCC III - AZ-EQ5 GT - ASI 533 MCP - Altair triband filter

best 108 of 120x30s unguided - Gain 200  - uncropped

[therion82]

M31 - the Andromeda galaxy
Exposure time: 30x45sec
telescope: sw 130pds
mount: celestron cg5
camera: canon 1100d
from bortle 6 sky, in Athens, Greece
Stacking and processing with Siril
 

[bosun21]

On 12/06/2022 at 18:35, Space Oddities said:

For anyone interested, I recently ordered a 3D printed copy of this mask, designed to block the stray lights coming from the back. It fits perfectly!

The material I selected might be a bit fragile though, perhaps I didn't select the best material and density for the job, but I don't know anything about 3D printing... Let's see if it holds!

Skywatcher 130PDS Primary Mirror Back Cover by RolandKol - Thingiverse

A black shower cap works a treat also 

[bosun21]

On 18/06/2022 at 10:33, Rob F said:

I love the PlayerOne camera, I have the Neptune C and plan on getting the new Saturn C (imx533 sensor). As for tilt, the PlayerOne has screws to adjust tilt.

My M51 was taken with PlayerOne, 60s subs for 10.5hrs total.

Which one of the player one cameras do you recommend for someone moving from visual into AP? with a 130PDS.

[Rob F]

12 hours ago, bosun21 said:

Which one of the player one cameras do you recommend for someone moving from visual into AP? with a 130PDS.

Depends on what you want to image. PlayerOne has released a couple of new cameras with larger sensor, the Saturn uses the square format imx533 which I hope to get when it’s in my budget.

For planets I’d say the smaller sensor would be better. Exposure times will depend on if you’re guiding or not.

[Rob F]

Some images of very short imaging sessions over past two weeks, mainly due to guiding and mount issues. I also wanted to see if my PlayerOne camera does well on nebulae, the Veil Nebula was less than 20min of data. 
I also imaged my fave dso type, star clusters, M10-M14 as well as M71. 

Edited July 20, 2022 by Rob F

[Rob F]

I forgot to add The Eagle Nebula image.

[Jim Smith]

Messier 52 and the Bubble Nebula in Cassiopeia

 

130 pds - Baader MPCC III - AZ-EQ5 GT - ASI 533 MCP - Altair triband filter

best 40 of 44x120s - guided - Gain 100  - uncropped

[Uranium235]

On 21/07/2022 at 12:16, Jim Smith said:

Messier 52 and the Bubble Nebula in Cassiopeia

 

130 pds - Baader MPCC III - AZ-EQ5 GT - ASI 533 MCP - Altair triband filter

best 40 of 44x120s - guided - Gain 100  - uncropped

 

Just out of interest, do you guide? Im just wondering why, with your camera (zero amp glow), you arent pushing the boat out a bit more with the sub length? For narrowband I'd be doubling or tripling the expoure time as a minimum.

Its just, if the previous hurdles of cmos (ie: amp glow) have been removed, I (personally) would be caning that sensor for all its worth in terms of sub length. Or at least taking each sub to the point of whatever maximum exposure the optics, or location will alllow.

Try 300s or even 450, you can still generate a decent stack in one hour (8 subs is enough to work with sigma clipping routines, but 16 is better). Youve obviously got the scope nailed because you done some decent images with it - but it will give you more if you give it more time on target. Its not just the main target that needs to be clean, but all the fluff that surrounds it    youre only gonna get that with long subs mate.

If theres a technial limitation of the camera, id be interested to know because I was eyeing up the mono version.

[Jim Smith]

1 hour ago, Uranium235 said:

Just out of interest, do you guide? Im just wondering why, with your camera (zero amp glow), you arent pushing the boat out a bit more with the sub length? For narrowband I'd be doubling or tripling the expoure time as a minimum.

Its just, if the previous hurdles of cmos (ie: amp glow) have been removed, I (personally) would be caning that sensor for all its worth in terms of sub length. Or at least taking each sub to the point of whatever maximum exposure the optics, or location will alllow.

Try 300s or even 450, you can still generate a decent stack in one hour (8 subs is enough to work with sigma clipping routines, but 16 is better). Youve obviously got the scope nailed because you done some decent images with it - but it will give you more if you give it more time on target. Its not just the main target that needs to be clean, but all the fluff that surrounds it    youre only gonna get that with long subs mate.

If theres a technial limitation of the camera, id be interested to know because I was eyeing up the mono version.

It is the very first time I have got autoguiding to work. I always used to used to take 30s, perhaps 60s subs. 120s is very daring for me! It looks like I can go longer now. But tell me why fewer longer subs are better than more shorter ones.

[Uranium235]

8 hours ago, Jim Smith said:

It is the very first time I have got autoguiding to work. I always used to used to take 30s, perhaps 60s subs. 120s is very daring for me! It looks like I can go longer now. But tell me why fewer longer subs are better than more shorter ones.

Ahh, so youve yet to ramp up your guiding - I get it. Once youve cracked 15min subs you get sense of satisfaction

As for long vs short subs... Im not really going to open the whole debate on lucky imaging as both ways have their merits and detractors. But the main reason for going longer is the S/N ratio of each sub would be better, meaning that the fainter details... those fluffy bits of Ha and dust contain less noise to start off with. You can still generate a big stack if you want (40+subs), but if the noise isnt there in the first place, you dont have to work so hard to remove it.

When you start chasing more difficult things, you may find what you are trying to process is barely above the background level (eg: the IFN), so its not just long, but lots as well. Earlier CMOS camers didnt do so well with long subs, but now the amp glow problem has been removed  it means you can go without darks and stack on the fly - to assess data as it comes in (which is how I work)

Major downside to it, one plane, gust of wind, car headlight etc, can ruin a long sub easily.